Abstract : Central areolar choroidal dystrophy (CACD) is a rare inherited disease, which causes progressive profound loss of vision in patients during their fourth decade. It is characterized by atrophy of retinal pigment epithelium, photoreceptors and choriocapillaris. The disease showed a genetic heterogeneity. Previously, mutations in the peripherin/RDS gene and a linkage to the CACD locus in the 17p13 region have been reported in CACD families. In this study, we report on a clinical and genetic investigation of CACD in a large Tunisian consanguineous family with 21 affected individuals in three living generations. CACD has been associated with drusen in some of them. Linkage analysis and mutational screening exclude linkage to the PRPH2/RDS gene and to the CACD locus. These data provide further evidence of the genetic heterogeneity of CACD. Journal of Human Genetics (2009) 54, 589-594; doi:10.1038/jhg.2009.82; published online 21 August 2009